Interview Q&A / JavaScript
JavaScript interview questions
Closures, the event loop, this, promises and the core language questions every frontend round asks.
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- What is the difference between var, let and const? Explain hoisting and the temporal dead zone.
var is function-scoped and is hoisted with the value undefined. let and const are block-scoped and are hoisted too, but cannot be used before their declaration line; that gap is the temporal dead zone. const also cannot be reassigned, though an object it holds can still be changed.
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